1. Field of the Disclosure
The disclosure relates in general to a partial lens shading compensation method.
2. Description of the Related Art
Image sensors are usually implemented by an array of photodiodes, or by so-called pixels. The pixels itself, instead of retrieving colors from light beam, convert broadband spectrum photons into electrons. In order for a single image sensor to record color images, a color filter is used to filter the incident light so that different pixels can detect different colors. Different color filters have different arrangements on the image sensors, and the Bayer arrangement of color filters is widely used in various applications. For a Bayer filter, there is a filter pattern which is 50% green, 25% red and 25% blue. For retrieving color information, red, green, and blue color filters have a particular arrangement on the image sensors for forming a repeating unit. For a Bayer filter, there is a repeating unit of 2×2 grid.
However, due to the geometric arrangement of the pixel array, color filters of different colors correspond to different shading functions, thus causing current portable image sensors to generate image distortion.